Bleaching of a Thin Absorbing Liquid Layer by a Laser Radiation Pulse

The “bleaching” of a strongly absorbing liquid by a short laser pulse is investigated for various layer thicknesses on the assumption that the quantum-mechanical and specific (per molecule) optical parameters of the liquid are constant. The temporal and spatial distributions of the basic parameters of the liquid (temperature, pressure, internal energy, and velocity) and the radiation intensity are obtained. For the dependence of the water transparency function on the pulse energy satisfactory agreement between the theoretical results and the experimental data is established. The interaction between water and beams with Gaussian and annular transverse intensity distributions is studied. It is shown that the experiments with annular distributions can provide additional confirmation of the hydrodynamic mechanism of liquid bleaching by a laser beam.